Nikon SMZ1000 Instruction Manual page 16

Insert the eyepieces into the eyepiece sleeves.
9
Be sure that it is inserted all the way until it touches the end of the sleeve.
Note) When inserting the eyepiece, hold the rubber cover of the eyepiece.
The hexagonal wrenches and clamp tool can be stored in the
10
pillar of the stand.
Refer to the figures on p.9 and p.11.
14
Holding the diopter ring causes a failure. Especially, be careful
with the 10X eyepieces because their rubber covers obstruct the
view of the sleeve end.
Assembly
II